After a cooler, and wet Christmas, temperatures in Batemans Bay, Nowra and Kiama for the New Year weekend are expected to be in the low 30's.

Sunday, January 2 is forecast as the hottest day of the week, with temperatures above 30 degrees along the South Coast and Southern inland regions.

The mercury will reach as high as 37 degrees around Yass and Goulburn on Sunday.

Meanwhile, people in the Southern Highlands can expect a slightly more comfortable temperature of 28 on New Year's eve and New Year's day with a rise to 31 degrees on January 2.

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Further north, in Foster and Taree, cooler temperatures are expected, with maximums of 27 and 28 degrees.

It's unusual for the south coast to exceed the northern NSW coast's temperatures, however the warmer conditions aren't unusual for this time of year and shouldn't be alarming, according to the Australian Bureau of Meteorology (BoM).

According to a post on the BoM Facebook the recent heat wave affecting Western Australia is moving east, bringing hot days and warm nights, especially to the southern parts of NSW and further south into Victoria, Tasmania and the ACT.

The Bureau expects the warm weather to remain for several days, including muggy conditions at night as temperatures stay uncomfortably high. Forecasts of a wet La Nina summer remain: the rain is expected to return in weeks to come.

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BoM is reminding residents that warm temperatures also increase fire risk, and post a challenge to some, particularly vulnerable and elderly citizens.

They recommend making sure you and your pets are staying cool and hydrated in the heat.